A tube-type endoscope may inflict great pain and discomfort on a tested person during endoscopy. In order to remove the disadvantages of the tube-type endoscope, a capsule-type internal image photographing apparatus (hereinafter, a capsule-type endoscope) has been developed.
When a tested person swallows a capsule-type endoscope like a pill, the interior of internal organs is photographed by the capsule-type endoscope, and photographed data is stored in an additional storage device. After photographing is finished, a medical doctor may confirm the photographed data using a computer.
FIG. 1 is a cross-sectional view of a capsule-type endoscope that has been disclosed in Korean Patent Laid-open Publication No. 2003-0025222 entitled ‘Internal image photographing apparatus and system’ (hereinafter referred to as a conventional endoscope 200).
Referring to FIG. 1, the conventional endoscope 200 includes an image photographing system 130, which is comprised of a light source 100, a complementary metal oxide semiconductor (CMOS) image sensor (CIS) 110, and a lens 120. The light source 100 functions to irradiate light to an inner wall of the internal organ. The light source 100 is a light emitting diode (LED). Also, the lens 120 functions to condense light reflected by the inner wall of the internal organ on the CIS 110. The CIS 110 functions to convert an image received via the lens 120 into an electric signal. The conventional capsule-type endoscope 200 further includes a pair of batteries 140 for supplying power and a wireless transmitter 150 for transmitting an image signal detected by the CIS 110 to an external wireless image recording apparatus. The image photographing system 130, the batteries 140, and the wireless transmitter 150 are hermetically sealed by an exterior material 160. In this case, the exterior material 160 includes a dome-shaped transparent plastic material for enclosing the image photographing system 130 and a metal material for enclosing the batteries 140 and the wireless transmitter 150.
When a tested person swallows the conventional capsule-type endoscope, the capsule-type endoscope may give an extraneous feeling to the tested person. Also, the conventional capsule-type endoscope may have the following problems.
First, since the conventional capsule-type endoscope can photograph only long-distance regions, regions to be photographed may be limited. For example, when the interior of an internal organ having a wide internal space, such as the stomach, is photographed using the conventional capsule-type endoscope, it is difficult to photograph regions of the stomach near the endoscope. Even if the regions of the stomach near the conventional capsule-type endoscope are photographed, it is difficult to obtain significant information from low-resolution photographed images. Also, it is impossible to photograph regions to be seen in a reverse direction to a direction in which the endoscope proceeds. Also, since the conventional capsule-type endoscope passes through the stomach in a short amount of time, it is also difficult to take high-resolution images of long-distance regions.
Second, the conventional capsule-type endoscope has no directionality. In other words, the conventional capsule-type endoscope moves passively according to the peristalsis of the internal organ, which thereby substantially determines the direction of the lens 120 and the CIS 110. As a consequence, the image photographing system 130 of the conventional capsule-type endoscope photographs images in an arbitrary direction, so that it is difficult to photograph desired portions.
Third, when using the conventional capsule-type endoscope, it is troublesome for a tested person to carry an additional image storage device for a long amount of time in order to store photographed images. Furthermore, since the image storage device is expensive, it may be an economical burden on the tested person.